During magnetic disk manufacturing, disk surfaces are exposed to various sources of contamination. For example, different gases, chemicals, deposition materials and dust may end up as contaminants. These contaminants may be deposited on the disk surfaces in particulate or other forms and must then be removed during one or more stages of the manufacturing process.
Contaminants are typically removed using a combination of sonication and rinsing techniques. A disk may first be submerged in a sonication cleaning tank to loosen and remove contaminants, and then moved to a rinsing tank where the remaining contaminants may be carried away from the disk surfaces. Conventionally, there is no real-time mechanism for measuring the efficiency of these cleaning processes. Thus, there may be relatively little feedback for an operator to determine that the disks are not being cleaned effectively or to detect failure in one or more components of the cleaning apparatuses.